No. 10. Victoria Justice
Birthdate: Feb. 19, 1993 (age 18)
Why She's Hot: You probably most recognize her as Tori Vega from the Nickelodeon's show "Victorious," which is about to enter its third season, but this Hollywood, Fla. native is racing up the album charts too. In August, she made big impact on the Billboard 200 album chart with a No. 5 debut for the "Victorious" soundtrack, which featured Justice on almost every track. With her first solo album and an appearance on the forthcoming "Footloose (2011)" soundtrack - a re-recording the classic duet "Almost Paradise" with country up-and-comer Hunter Hayes - in the works, Victoria is eyeing for an even higher rating on next year's under-21 list.